I develop a desktop application, and I'd like to add a "question mark" icon besides one of the textbox (that describes the meaning of that textbox).

My question is what the common way to use the question mark is: Should I show the text when hovering on the question mark? E.g. using a tooltip? Should I show the text just after clicking on the question mark?

2 Answers
2

It is better to show standard short hint (if possible) when hovering over question mark, more expanded -- by clicking it (to prevent accidental expanding when moving cursor from one area to another).

Also, if necessary, sometimes it is good to add at the end of the expanded tooltip link to detailed info at help part of service.

Also avoid such behaviours, as moving expanded tooltip with cursor -- such gluing is rather frustrating, and [x] inside it to close -- any mouse click or touch event outside the hint should hide it, and [x] makes user feeling to target cursor on the cross and click it to close the hint -- what is rather not optimal behaviour due to the scale of the control.

Assuming this is an application for the Windows environment you should try to abide by the Windows User Experience Interaction Guidelines . This includes sections on how one should design help features, or more wittier put; a section which describes how to:

Use Help as a secondary mechanism to help users complete and better understand tasks—the primary mechanism being the UI itself.

From what I understood it seems to be very context dictated, and how large quantities of information you expect to display. You don't want to open a modal window that has the potential of obstructing a user and which only reads E.g. "Enter the year you were born", since that would be an overkill. But neither want to present a large chunk of text to a user in a tooltip which risks disappearing as soon as the user moves the mouse.

I suggest taking a look at the guidelines to find a solution that corresponds with the type of help you intend to show.